New detergent washes away stains of murder: study

MADRID (Reuters) - A new generation of cleaning products could help criminals get away with murder by making bloodstains invisible to forensic tests, Spanish researchers said Wednesday.

A team at the University of Valencia found that new washing powders and other chemicals that generate oxygen rather than use chlorine erase telltale traces of hemoglobin, the protein inside blood that transports oxygen around the body.

Police often rely on blood-splattered clothing to link a murderer to a crime. Even after 10 washes, forensic experts have been able, up to now, to identify blood using a cocktail of chemicals to unmask the stains.

But new detergents like Reckitt Benckiser's 'Vanish' that contain the active ingredient sodium carbonate peroxyhydrate produce a fizz of oxygen bubbles that degrade blood even though the stain may remain visible to the naked eye, according to the study published in the German journal Naturwissenschaften and reported in the New Scientist.

Fernando Verdu, a forensic scientist at the University of Valencia, said his three-member team would next investigate if the new oxygen-producing chemicals also destroyed DNA, which can provide crucial evidence in murder investigations.

"The majority of criminals are not that smart. They don't do things as you expect them to and read this kind of news. It is very simple to commit a crime, the difficult part is to not get caught," said Verdu.